Numerical analysis of free folding of flat textile products and proposal of new test concerning bending rigidity

Abstract

Free folding of flat textiles has been studied by means of elastica for the same shape and folding conditions across the product. Elastica is described using the system of six first-order differential equations accompanied by a set of boundary conditions. The problem is solved by the shooting method and divided in two stages. The shooting method is ineffective for some parameters, and the process is divergent which is clarified by sensitivity analysis. The proposal adopts the width of fold as a measure of bending stiffness (C) and the sample is now subjected to bending in both directions in a wide range of curvatures. This is alternative to the Peirce’s test, in which the test specimen is subjected to a slight bending in one direction only. The Peirce’s test gives the unprecised results under some loadings. This study presents a detailed sensitivity analysis of some process parameters to describe the unique solution for bending problem of textiles. It is also proposition for new test for bending rigidity of textiles.